From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794591061; b=S/kntzDQDwWb7byYnkajpUehHXNQ0iYQKWLzTP0K2Nl7bSF5AiOmth45f/5klQaYDsTC vCV4NaeQS0/qjEI2jSNTHVP6U09m3SQimWcyXQBfV/zde4WfFWFsDTpbgvo+FH4nVPu2y HorTZonxXzrLgiCism7liuLBEYT30LS2PQVDLBNz9w0AcdVdOCEC7/DTmxMId+mesLvBf 7AhGfFL2RW2WuRtVb+7noCXjXR4k57zYjy3o3cEDlQ6P72kF22c5sUJX8Ob7rJn7D6G+L 9tTodv2qV4EC8efz/aXWdbTreoP3ytxrYtWThbOi7yZu0W6hCfkiYhquoadCZwe1nqw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794591061; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=JeEgAOxyGlB5EYojL7pyyoH7fE58/gFW5a/TotggxOI=; b=vxZNG3+o4auEFmTXUsUNu8lXFOi6QMcT4cWtYXakdZjqSEr7WeK1k5sDPfj5oz/Y7xO4 zf6wpWBRci9m2/QkwdHtKVO9wwt7IHGKNjglKmK976n8itUNG7cPR2LOfMVQ+uH4MZSvQ xjEGCKFF2wxRMI/yJ0VWznSAwnodgR0Voyo0VcG4kgAEFvWZcj5b1IiaAmJshrxoBLIZ/ ojsf/hDZtJw2Y0N02UlrOjGhdF9sc3zX4LqJfgX04si2HwByuTya0tSK0iRpthsXHt1oF coKuIrugWM/cDNprd8XYIhrjzkIqnrYnBET7WDlpxJRiCgH3gCvPE0b+WbA1I9fNfaw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=EvDT07qS; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C3C6D606B83B; Fri, 13 Nov 2026 17:31:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=EvDT07qS Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6FF771F000C5; Fri, 13 Nov 2026 17:31:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794591061; bh=JeEgAOxyGlB5EYojL7pyyoH7fE58/gFW5a/TotggxOI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=EvDT07qSbBC9Sx70NGKnOXEE2QIxJAr6DgYc9xGulO5kNSOYg/7iE2i0J7pXYn3hK QRGOL7/hmd5NsKwc6jhiReBJRBu+kHAlyDqZ99mfbCEmHMELaS4bA1VBdIh5JQqr+N sSQSY0PGqQfv9gd1Q5GRucv+vBmYUcgwMm2kBJ7s= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Namjae Jeon , Ian Bridges , Sasha Levin Subject: [PATCH 6.12 221/670] ksmbd: grant a POSIX ACL group entry only to the groups members Date: Fri, 13 Nov 2026 10:46:25 -0500 Message-ID: <20261113153819.381110694@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261113153811.177190860@linuxfoundation.org> References: <20261113153811.177190860@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ian Bridges [ Upstream commit c00ec7ad449b68c291a4986e481941302ed399c5 ] When no ACE of the DACL matches the caller, Everyone or Authenticated Users, smb_check_perm_dacl() falls back to the file's POSIX ACL. It takes the first ACL_USER or ACL_GROUP entry whose id equals the caller's uid. For ACL_GROUP, this compares a gid with the caller's uid. A numerical match grants the group's permissions even when the caller is not a member. Match a group entry only when the caller is also in the group. Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3") Reported-by: Namjae Jeon Closes: https://lore.kernel.org/linux-cifs/CAKYAXd93czbFD=znZUq_pJLXzDR5N3zc_auvAGWT7pzKR1f9Ag@mail.gmail.com/ Cc: stable@vger.kernel.org Signed-off-by: Ian Bridges Signed-off-by: Namjae Jeon Signed-off-by: Sasha Levin --- fs/smb/server/smbacl.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/fs/smb/server/smbacl.c b/fs/smb/server/smbacl.c index 33a607e709f18..63f7bccb4d9af 100644 --- a/fs/smb/server/smbacl.c +++ b/fs/smb/server/smbacl.c @@ -1606,7 +1606,10 @@ int smb_check_perm_dacl(struct ksmbd_conn *conn, const struct path *path, else continue; - if (id == uid) { + /* A group entry grants only to the group's members */ + if (id == uid && + (pa_entry->e_tag == ACL_USER || + in_group_p(make_kgid(&init_user_ns, id)))) { mode_to_access_flags(pa_entry->e_perm, 0777, &access_bits); -- 2.53.0